Running a Ragnar relay is unlike any other race experience you've ever had. While your team has a start time, the time you actually start running might be one, five, eight hours later, so you're kind of all-day prepping for a race start. You could run at 8 am and 3 the same afternoon and then again at midnight, so how do you fuel up? When do you sleep (spoiler: not much, if at all).
There are enough logistics to throw a race-day-prepper for a total loop, so how on earth do you keep yourself straight when you're out of whack with your normal race morning prep? My best advice: make sure you've got it all - everything you'll definitely need, everything you think you'll need, and everything that you've never thought about needing because at some point, it will come in handy. Trust me.
I created this Ragnar packing list for you to help keep yourself straight for 20-something hours of fun. Link leads to downloadable PDF - share away, I just ask that you keep my handle and info on the page if you share/re-post the images!
That's about it. I'll also add to the Van Supplies a food list for your team. Consider community snackage over everyone bringing their own thing (and therefore more coolers). Team essentials will vary team to team, but I've always found myself with tons of leftover snackage for drives/flights home, which is never a bad thing in my book. Better to have too much food that to wake up starving in a van driving through Maryland countryside at 2 am with nothing open, right?
Good luck on your Ragnar adventure!